1. Field of the Invention
The present invention relates to a synthesis method for a self-dispersible pigment, a self-dispersible pigment, an ink jet ink, an ink cartridge, and an ink jet recording method.
2. Description of the Related Art
In general, a pigment alone is hardly dispersed in a dispersion medium. Thus, various studies have heretofore been made to obtain a stable pigment dispersion. For example, the dispersion stability of a pigment in various dispersion media has been enhanced by using a resin or a surfactant as a dispersant for dispersing the pigment. For example, Japanese Patent Application Laid-Open No. H08-143813 proposes a print ink using, as a pigment dispersant, a resin having a graft structure in which a polyester chain as a side chain is bonded to a main chain constructed of a polyamine. In addition, Japanese Patent Application Laid-Open No. 2008-524400 describes an attempt to enhance dispersibility of a pigment itself in a dispersion medium by bonding an ionic group to the surface of the pigment particles by a chemical treatment.
In recent years, an ink jet recording apparatus has been frequently used in an office or a home. Under such circumstances, demands for abrasion resistance of an image have been increased. In order to overcome this problem, various attempts have so far been made. For example, Japanese Patent Application Laid-Open No. 2004-143272 proposes a combination use of a self-dispersible pigment with an emulsion of a resin having a polyester structure as ink components.
Further, Japanese Patent Application Laid-Open Nos. 2003-519709 and 2008-531762 each propose modification of a pigment by chemically bonding a resin to the surface of a pigment particle in addition to covering the pigment with the resin to form a microencapsulated pigment.